•ZnO/α-Fe2O3 composite deposited on plasma chamber wall (ZF-W) are investigated.•ZF-W is compared with plasma treated mixture deposited on target substrate (ZF-S).•Structural studies are conducted by ...XRD, TEM, PL, Raman and Mossbauer spectroscopy.•Cationic arrangement and oxygen vacancy defects play a role in structural variations.•ZF-W shows excellent methyl blue adsorption without any external light sources.
While conventional cleaning to remove the coating from plasma chamber walls becomes essential to reproduce the desired materials on the target substrate for widespread applications, an attention towards wall-deposited materials is scarce. Recycling those waste materials to value-added product is of great importance for sustainable progress of our modern society. Herein, we investigated the materials deposited on the wall of plasma chamber, explored their promising features and compared them with conventionally grown materials. A mixture of ZnO and α-Fe2O3 (ZF) exposed to high energy plasma was collected from the wall (ZF-W) and also from the substrate (ZF-S) to check the feasibility of providing same quality products. With same lattice constant of hematite, magnetite and zinc ferrites, ZF-W differs from ZF-S in coercivity, saturation magnetization, ferromagnetic stoichiometry and defects. In addition, degradation of Methyl Blue (MB) dye in ZF-W without use of any external light sources are comparable, more stable and durable in comparison to ZF-S. The slight differences obtained in the property-performances between ZF-W and ZF-S are attributed to the cationic arrangement and the oxygen vacancy defects present in the structure. The study reflects the potentiality of ZF-W as a promising active material for wastewater treatment just as one can use ZF-S. These findings clearly depict that the unused products with altered intrinsic properties obtained after plasma treatment has similar or even better potential to its actual targeted product and thus can be utilized properly thereby saving cost and time and, hence generates an unexplored direction for the materials science community.
Display omitted
While conventional cleaning to remove the coating from plasma chamber walls becomes essential to reproduce the desired materials on the target substrate for widespread applications, an attention ...towards wall-deposited materials is scarce. Recycling those waste materials to value-added product is of great importance for sustainable progress of our modern society. Herein, we investigated the materials deposited on the wall of plasma chamber, explored their promising features and compared them with conventionally grown materials. A mixture of ZnO and α-Fe2O3 (ZF) exposed to high energy plasma was collected from the wall (ZF-W) and also from the substrate (ZF-S) to check the feasibility of providing same quality products. With same lattice constant of hematite, magnetite and zinc ferrites, ZF-W differs from ZF-S in coercivity, saturation magnetization, ferromagnetic stoichiometry and defects. In addition, degradation of Methyl Blue (MB) dye in ZF-W without use of any external light sources are comparable, more stable and durable in comparison to ZF-S. The slight differences obtained in the property-performances between ZF-W and ZF-S are attributed to the cationic arrangement and the oxygen vacancy defects present in the structure. The study reflects the potentiality of ZF-W as a promising active material for wastewater treatment just as one can use ZF-S. These findings clearly depict that the unused products with altered intrinsic properties obtained after plasma treatment has similar or even better potential to its actual targeted product and thus can be utilized properly thereby saving cost and time and, hence generates an unexplored direction for the materials science community.
The plasma deposition wall coated composite of ZnO and {\alpha}-Fe2O3 (ZF-W) after exposure to ~ 2000 {\deg}C, mostly considered as waste-materials and cleaned out from the deposition unit, was ...subjected to anneal at 300, 500 and 1000 {\deg}C to manipulate the structural properties. An evolution of defect states along with the structural changes has been identified as annealing temperature was varied. As a consequence, an unstable state of ZnFe2O4 was found to be stabilized at 500 {\deg}C and migration of Zn from ZnO causes the phase transformation from the {\alpha}-Fe2O3 to ZnFe2O4. While implemented for methyl blue adsorption/degradation without the effect of any external sources, the degradation for ZF-W annealed at 300 {\deg}C, 500 {\deg}C and 1000 {\deg}C were 84%, 68% and 82%, respectively. Compared to annealed structures, pristine ZF-W delivered the highest methyl blue adsorption efficiency of 86%. The changes in adsorption/degradation properties have been correlated with the simultaneous evolution of defects and structural properties of ZF-W as annealed at different temperatures. The plausible mechanism on the interaction of methyl blue with the composites on the adsorption/degradation is proposed. These findings give a clear indication on the importance of defects presence in the mixed metal oxide composite to obtain high-performance degradation/adsorption properties for sustainable wastewater treatment.
PDF